To compile the recently issued Salary Negotiation Guide, PayScale asked 31,000 people whether they'd ever negotiated their salary. Fifty-seven percent said they had not. Given that not negotiating salary can cost you hundreds of thousands of dollars over the course of a lifetime -- and that 75 percent of people who ask get at least some kind of salary bump -- it obviously makes sense to hit the bargaining table before you accept a new job offer or let your annual review go by without initiating a discussion about money. Still reluctant? Arm yourself with the facts.

What's the biggest mistake you've made in your career? If you're like most of us, it's not learning from your other errors. This week's roundup looks at what makes moguls like Mark Zuckerberg different from the average person, how exercise can help your career, and whether or not layoffs are as bad for companies as they are for workers.

No one likes negative feedback -- either receiving it, or giving it. In fact, we might hate giving constructive criticism more than getting it; leadership development researchers Jack Zenger and Joseph Folkman found that while 92 percent of respondents to a survey valued corrective feedback, most managers felt uncomfortable giving it. Comfort levels aside, it's obviously unlikely for performance to spontaneously improve, without direction from leaders. So what can you do, as a manager, to offer negative feedback that leads to positive results?

"The shadow of crisis has passed," said President Obama, in last night's State of the Union address. "And the state of the union is strong." While receiving standing ovations for job numbers (and getting in an ad-libbed dig at Republicans about winning the presidency), Obama outlined a vision for the country that focused on middle-class growth.

If you could go back in time and give your younger self career advice, what's the one thing you'd say? For some, it would be to negotiate a higher salary or start investing more heavily in a 401k. Others might go all the way back to college and follow their dreams -- or pick a career with a better occupational outlook, and fund their personal projects that way.

Sometimes, the job interview process feels like the worst parts of dating. So much depends on having good instincts and good luck, and no matter how clever you are, you're always going to be plagued with at least a little self-doubt. This week's roundup kicks off with advice that will help job seekers avoid overdoing the follow-up after an interview. (Plus: tips on goal setting after your New Year's resolutions fail and more insight into why the gulf between older and younger workers sometimes seems so huge.)

In 20 states and the District of Columbia, the New Year meant higher wages for the lowest-paid workers. For states like Arkansas, Hawaii, Maryland, Nebraska, South Dakota, and West Virginia, the hike means that minimum-wage employees will make more than the federally mandated minimum of $7.25 an hour for the first time ever.

Ask anyone who's ever paid out-of-pocket for their health insurance: benefits are important. It's too bad, then, that we often overlook benefits when we're negotiating salary. PayScale's recently published Salary Negotiation Guide examines all the factors that go into making up a compensation package that reflects your skills and experience, not just base pay. Keep these in the back of your mind the next time you're negotiating an offer, and you could wind up earning more, saving money, and enjoying better work-life balance.

More than half of respondents to PayScale's salary survey have never negotiated their salary, according to data gathered for our recent Salary Negotiation Guide, despite the fact that 75 percent of those who asked received a bump in pay, and 44 percent even got the entire sum they requested. Furthermore, research suggests that many of the non-negotiators consider themselves to be underpaid. So why don't people ask more often?

New year, same old career? If you ever needed proof that January 1 is just a day on the calendar, the week after the holidays might provide it. But just because the beginning of a new year isn't automatically a new start at work, doesn't mean that you can't use the fresh page in your planner to inspire you to make changes, large and small, that can make 2015 the best year of your career so far.

Why is it so scary to ask for what you deserve, especially when it involves a dollar amount? For one thing, we live in a society where talking about money is considered tacky, as is blowing your own horn. To get the salary that's appropriate for our experience, skills, and capabilities, you need to get comfortable doing both. PayScale's Salary Negotiation Guide helps you feel more secure asking for a raise or establishing your starting pay by breaking the process into three parts: research, strategy, and negotiating.

Ahead of this morning's ADP National Employment Report, economists predicted the addition to private payrolls of 225,000 jobs. The report, which is jointly produced by Moody's Analytics and payroll processor ADP, showed higher gains than expected -- 241,000 jobs in all. In addition, last month's payrolls were adjusted upward from 208,000 jobs to 227,000 jobs.

A long time ago -- or maybe it only feels that way -- our careers were at their beginning. Full of promise, ambition, and possibly misplaced self-confidence, we embarked on our journey up the corporate ladder. The luckiest among us received plenty of advice from the wiser and more experienced people in our lives, whether they were our parents, teachers, first bosses, or friends. If we were really fortunate, we were even able to hear it.

Possibly the only upside to being unemployed, as long as it doesn't go on too long, is finally having enough time to take care of your living space and spend time with your children, if you have them. But as The Upshot's Josh Katz recently discovered, even unemployment looks different, depending on whether you're a man or a woman.

When you feel confident, the people you interact with in your career are more likely to reward you with the things you want, whether it's a job or a promotion or a raise or a parking space closer to the front door. This is potentially pretty unfair, of course, since anyone who's worked with other humans for more than a day knows that confidence isn't always an indicator of competence. So what can you do, if you're deserving, but underappreciated -- and not burdened with an excess of self-regard? Game the system, and fake it until you make it.

Do you feel a subtle pressure to get in to work early? It's not in your head. Many companies create a culture that rewards long working hours. The problem, according to a new study from the University of Pennsylvania Perelman School of Medicine, is that getting up with the roosters often means cutting down on time spent sleeping.

Depending on how 2014 treated you, the dawn of a new year is either a welcome chance to start over or an opportunity to continue building on what you're already creating. Either way, it's a good time to engage in a little self-reflection, so that next year brings you more of what you want in your career and your life, and less of what drove you crazy during the past 12 months.

Even if you don't observe any of the December holidays, personally, there's almost no way you've made it this far into the month unscathed by the gift-giving madness. Now that all of the bustling and spending has come to end, it's time to turn your attention inward, and ask yourself what you need and want in the next year, in order to get the career you deserve. Good news for your bank account: many of these "gifts" are free.